How come the human brain remembers music lyrics from years ago?

I was just wondering why the human brain seems to retain song lyrics for a very extended amount of time. I'M only 17 now but I can remember song's from over 9 years ago and I know the lyrics right when I hear them. But when you try to remember someone from a few weeks ago you don't really know. Is this caused by the songs get listened to so many times that it gets imprinted in your long term memory?